5-Membered rings – 2N 3057-amino-4,6-dinitrobenzofuroxan (77) (ADNBF) is more impact insensitive than 4,6-
dinitrobenzofuroxan. ADNBF (77) has been prepared^48 from the nitration ofm-nitroaniline
(75), followed by reaction of the product, 2,3,4,6-tetranitroaniline (76), with sodium azide in
acetic acid; the latter reagent resulting in displacement of the labilem-nitro group of (76)
and spontaneousin situcyclization of the resultingo-nitroarylazide. ADNBF has also been
synthesized from the nitration of 6-chlorobenzofuroxan, followed by reaction with ammo-
nia in methylene chloride.^48 A more unusual route to ADNBF involves the reaction of 4,6-
dinitrobenzofuroxan (DNBF) with a source ofN-formyl anion and oxidation of the resulting
Meisenheimer complex with nitric acid.^49 ADNBF has excellent overall properties (calculated
VOD∼7900 m/s,d= 1 .90 g/cm^3 and m.p. 270◦C) and is under advanced development in
the US.
ClNO 2
Cl
78Cl
79O 2 NCl N 3O 2 N NO 2ClCl
80N 3NO 2NO 2O 2 NClN
ONO 2Cl
81O 2 NN Cl
ONO 2NH 2H 2 NN O 2 NONNO 2N
O ON
ON
OHRO K+83, R = NHOH82
(DADNBF)NaN 3 , DMF 100 % HNO 3PhCH 3
heatPhCH 3 , NH 3- NH 2 OH.HCl,
KOH (aq) - H+
Figure 7.315,7-Diamino-4,6-dinitrobenzofuroxan (DADNBF) (82), an impact insensitive high perfor-
mance explosive (VOD∼8050 m/s,d= 1 .91 g/cm^3 ), has been prepared in four steps from
1,3,5-trichloro-2,4-dinitrobenzene (78),^50 and also by treating the Meisenheimer complex
(83)^51 with excess hydroxylamine hydrochloride in aqueous base. DADNBF has also been
synthesized in five steps starting from 2-nitroaniline.^51
2 N NH 2 O 2 NH NO 2ClCl
NO 2
85H
NH
NNO 2NO 2NO 2O 2 NO 2 NCl O 2 N ClH
NH
NCl Cl
H
NH
NNO 2NO 2NO 2NO 2NO 2
NO 2NO 2NO 2O 2 N NO 2O 2 NO 2 NO 2 NO 2 NO 2 N
O 2 NNO
N NO
NNaHCO 3
+8687- NaN 3
- heat, -N 2
8884100 % HNO 3 ,
H 2 SO 42OOFigure 7.32